Method of and apparatus for casting hollow bars or tubes



G. MELL EN.

METHOD OF ANG APPARATUS FOR CASTING HOLLOW BARS 0R TUBES. APPLICATION FILED MAY 14, 1919.

1,342,127. v Patented June 1, 1920.

2 SHEETSSHEET I.

e. MELLEN. METHOD OF AND APPARATUS FOR CASTING HOLLOW BARS 0R TUBES.

APPLICATION FILED MAY 14, 1919.

noun-ED sTAT PAT NT I OFFICE.

GRENvILLE iuELLEN, or cmronn; NEW JEns'EY.

METHOD OF AND APPARATUS FOR CASTING HEOLLOW BARS OR TUBES.

of New jersey, have invented certain new and useful Improvements in Methods ofand Apparatus for Casting Hollow Bars or Tubes, of which the following is a specifica tion.

, My invention relates to a method and apparatus for casting hollow bars or tubes and has for'its object to cast such hollow bars or tubes of lengths longer than can be obtained by the ordinary methods of cast ng in molds. t

It has heretofore been diflicult to make rod or tube castings of. certain alloys, such as bronze used for making bushings, in lengths relatively long as compared wlth the dlameter, because of the tendencyof this material to crack in the mold or to .form imperfect castings, also containing blow-holes and gas voids.

These difficulties I overcome bya method and apparatus which are basedpnthe pr n-' ciples of operation disclosed 1n my prlo'r Patents Nos. 1,139,885, 1,139,886, 1,139,887, 1,139,888 and 1,139,889, patented May 8, 1915, and in'my allowedappllcation Ser. No. 34,735, filed June 17, 1915,. r

' The invention will be understood from the accompanying drawings in which Figure 1 is a transverse vertical section through the casting tubes;

Fig. 2 is a vertical section on a plane at ri ht angles to that of Fig. 1;

' ig. 3 is a horizontal sectlon on plane 3-3of Fig. 2; and

Figs. 4, 5, 6 and 7 are cross-sectional views of various forms of tube-rodcastings.

The, machine shown is of the vertical type shown in my Patents Nos. 1,139,888 and 1,139,889, only such details-of construction being shown in the present appllcatlon as relate to this particular invention.

. In this type of machine, the mold cavity 3 is formed by and between two endless chains ofmold blocks having suitable shaped mold cavities therein. As shown in Flg. 3 the mold blocks B, B each have central and slde semi-cylindrical cavities, which when the blocks are brought into Inetal-seahng engagement form three connected vertical mold chambers, the central chamber bein shown of larger diameter than the side c ambers although this is not an essential feature.

Specification of Letters Patent.

MELLEN,

, chamber.

PatentedJune 1, 1920.

Application filed May 14, 1919. Serial No. 297,120.

I As shown in Fig. 1, the metal is delivered from the pouring pot 6 into the side chambers and flows into the central mold chamber wh ch is provided with a centrally located core, so thatfas the mold-chains move down- -ward,ther'e is formed a composite casting consisting of a central hollow or tube port1on connected to and integral with two solid rod portions.

The flow of metal from the pouring pot into the side mold cavities is controlled-by two valves 7, 7, mounted as shown in Fig. 2 on the ends of pivoted levers 80,.pivoted on bars 21, carried by a post 22. mounted on the frame of the machine. A spring or counterbalance 23 facilitates ease of operation. 24 is a suitable stop device. These valves may be operatedmanu'ally or by the automatic means described in my Patent No. 1,139,888.

The pouring pot 6 is provided-with two tubes 5 extending downwardly into the side mold chambers, and has an upwardly extending guide tube 20,. through which the cores are introduced into the central mold chamber. I 1 The cores are made in the usual manner and may consist of a core-barrel 3, of iron pipe with perforations through the, wall to permit the escape of gases to the interior of the pipe and their free escape out of the tubing having an interior diameter sufiicient to permit the insertion of the core-barrel and an exterior diameter fitting the central bore or mold chamber, these core-bits serving to center the core in this, central mold Mounted above the pouring pot is a tubular core guide 8, held'in position by stays 27 to the framework of the building or to the frame of the machine and by a guide ring 28. Turnbuckles 11 and adjusting screws 29 enable the core guide 8 to be properly centered.

The operation of the machine is as follows: To commence the operation, a piece of sheet metal is installed between the mold core' is then owered into the center bore, and

the end of the core-barrel inserted into the core-bit. A second core-bit is located on the upper end of the core-barrel and the lower end of a second core-barrel is inserted into the upper end of this second bit, this second core coming down through the coreguide 8. A succession of cores, centrally guided, is thus passed down through the central mold chamber.

At the proper time the valves 7, 7 are opened and molten metal flows down into the two side mold chambers and thence into the central mold chamber around the core to form the central tube. As the moldblocks move downward, the triple tube-rod casting 39 having the shape shown at the bottom of Fig. 1 and in Fig. 3 is produced and of any desired length. There is of course considerable latitude in respect to the cross-sectional configuration of the mold and the tube-rod pasting. 4, 5, 6 and.

.7 indicate various forms serving as examples. Figs. 4 and 5 show forms similar to that disclosed in Figs. 1 and 3, but differing as to the thickness of the webs cbnnecting the lateral rods with the central tube. Figs. 6. and 7 are modifications showing tubes interconnected by a 'central solid rod portion.

When a castin has been formed of the desiredglength, t e supply of metal is cut of and a newv casting ismade; or, the feed of'metal is stopped for a moment 'to allow a coating of oxid or scum to form on the top of finished casting, so that there will be no fusion to theend of the next casting as it comes along.

The central tube is severed from the -side rods by passing through suitable dies which cut the connecting webs, or the webs may be severed in any other suitable manner. By this method of casting, a sounder, denser product, substantially free from gblow holesor gas voids is obtained. The method is.

- moreover applicable to the casting of metals length than thirty-six times the diameter. The advantage of having such longer lengths will be apparent to those familiar with the art.

By the method of pouring into the side mold chambers, central tubes of relatively small diameter may be made; when larger tubes are desired it is feasible to pour the molten metal directly into the tube-forming chamber, since in such case there will be space enough to admit a feed tube into such chamber. 1 7

My method may further be varied, where the sectional areas are large enough, by extending cores into the side bores and feeding the metal throu h the center bore; but, I

feeding the metal rom both sides around the central bore has the advantage that the molten metal more rapidly envelops the core to form a tube.

I claim:

1. The method of casting tubes which consists in locating a core within a mold chamber formed by a series of traveling cooperating mold-sections, and delivering molten metal into said chamber about said core during the movement of the mold sections and the core located therein.

2. The method of casting rods or tubes which consists in delivering molten metal into a moving mold having severalmold forming bores therein, at least one of which has located-therein a central core, the metal being delivered into a rod-forming bore and %owing therefrom into the tube-forming ore.

3. The method as claimed in claim 2 in which the molten metal is delivered into two bores and. flows therefrom around the core in a central bore.

4. A casting machinecomprising a series Y of traveling sections fitting together toform a continuous mold chamber, a core arranged to travel with said traveling mold sections, and means for holding the core in position l(glaring its travel through said mold chamr. 5. A casting machine asclaimedin claim 4 in which the means for holding the core in position comprise tubes,v fitting over the ends of the core and fitting within said mold chamber.- 6. A casting machine comprising a series of traveling cocperative mold blocks fitting together to form a series of connected moldforming chambers or bores, means for centrally locating a core in at least one of said chambers, and means for delivering molten metal into said chambers.

i A casting machine as claimed in claim 6 in which the core is located in a central mold chamber, and a moldchamber is provided on each side of said central mold chamber.

7 having a pouring pot, and means for delivering molten metal therefrom into each of said side molding chambers.

9. A casting machine as claimed in claim 7 in which the central mold chamber is of larger diameter than the side chambers.

10. A casting machine as claimed in claim 6 having a tubular core guide arranged above one of said mold chambers.

11. A casting machine as claimed in claim 6 having an adjustable tubular core guide arranged above one of said mold chambers.

12. A casting machine as claimed in claim 6 in which the cores have barrels extending beyond the ends of the core covering, said ends extending into tubular core-bits fitting within the mold chamber.-

In testimony whereof I aflix my signature.

GRENVILLE MELLEN. 

